1. Field of Invention
This invention pertains to a step apparatus for vehicles and particularly to a step apparatus which is automatically operated upon the opening of a vehicle door.
2. Prior Art and Other Considerations
In recent years recreational vehicles (RVs) and light trucks have been sold in increasing numbers. These vehicles are now being used not just for light hauling and off-road trips, but also for commuting and general transportation purposes.
One of the primary features of these vehicles is their high road clearance. The purpose of the high road clearance is to facilitate off-road driving on rough and uneven terrain. The drawback of having such high road clearance is that embarking and disembarking the vehicle presents difficulty for certain passengers most notably the elderly, the infirm, children, and women wearing tight fitting shirts or gowns.
Previous attempts to overcome this problem fall into two basic categories; permanent steps and retractable steps. The first type of step has limited effectiveness since the closer the step gets to the ground the more the vehicle road clearance is compromised.
The second type of step, the retractable step, also has certain drawbacks. An example of a retractable step is shown in U.S. Pat. No. 3,751,068 to Green, wherein the step extends down and out by a cable attached to the hinged end of a door.
In the above regard, the Green patent does not disclose any way of adjusting the height or the number of steps. Furthermore, since the device patented by Green can only be used with vehicles which have hinged doors, it is not possible to use the device with sliding door vehicles. Finally, by attaching the cable to the hinged end of the door, the Green device has only limited energy available for extending the step since the distance of displacement of the cable is minimal.
U.S. Pat. No. 3,608,957 (Maneck) shows a running board for vehicles with sliding doors. The Maneck device, while satisfactory for use with sliding door vehicles, cannot be readily adapted for use with hinged doors. Maneck also does not disclose any way of adjusting the number and height of the steps.
Accordingly, it is an object of the present invention to provide an improved step for boarding vehicles.
An advantage of the present invention is to provide an improved step for boarding vehicles which can be used with both sliding door vehicles as well as with vehicles which have hinged doors.
A further advantage of the present invention is the provision of an improved step apparatus where the number and height of the step are adjustable.
A further advantage of the present invention is the provision of an improved retractable step assembly which translates energy used or produced in the act of opening and/or closing a vehicle door into energy for operating the retractable step assembly.